Electronic battery tester with battery clamp storage holsters

ABSTRACT

A battery tester includes a pair of battery clamps, a testing unit, and a pair of holsters. Each battery clamp is configured to connect to a terminal of a battery. The testing unit includes testing circuitry that is connected to the battery clamps, and is configured to perform one or more battery tests on a battery connected to the battery clamps. Each of the holsters is attached to a housing of the testing unit, and is configured to receive and hold one of the battery clamps.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is based on and claims the benefit of U.S. provisional patent application Ser. No. 62/964,834, filed Jan. 23, 2020, the content of which is hereby incorporated by reference in its entirety.

FIELD

Embodiments of the present disclosure generally relate to battery testing systems for measuring a condition of storage batteries and, more particularly, to a battery tester having holsters for storing clamps used to connect the battery tester to a battery.

BACKGROUND

Electronic battery testers generally use battery clamps for connecting the testing device to a battery for testing. Such clamps may each provide one or more connections, such as Kelvin connections, to the battery to facilitate the performance of one or more tests on the battery.

SUMMARY

Embodiments of the present disclosure generally relate to a battery tester having holsters for storing clamps used to connect the battery tester to a battery. In one embodiment, the battery tester includes a pair of battery clamps, a testing unit, and a pair of holsters. Each battery clamp is configured to connect to a terminal of a battery. The testing unit includes testing circuitry that is connected to the battery clamps, and is configured to perform one or more battery tests on a battery connected to the battery clamps. Each of the holsters is attached to a housing of the testing unit, and is configured to receive and hold one of the battery clamps.

In another embodiment, the battery tester includes a pair of battery clamps, a testing unit, a housing, and a pair of holsters. Each battery clamp is configured to connect to a terminal of a battery. The testing unit includes testing circuitry that is connected to the battery clamps, and is configured to perform one or more battery tests on a battery connected to the battery clamps. The housing includes a pair of magnets. Each of the holsters is attached to the housing, and includes a holster body having an interior cavity configured to receive and hold a clamping end of one of the battery clamps. Each magnet is configured to magnetically secure one of the battery clamps within the interior cavity of one of the holsters.

In yet another embodiment, the battery tester includes a pair of battery clamps, a testing unit, a housing, and a pair of holsters. Each battery clamp is configured to connect to a terminal of a battery. The testing unit includes testing circuitry that is connected to the battery clamps, and is configured to perform one or more battery tests on a battery connected to the battery clamps. The housing includes a pair of first connectors. Each of the holsters includes a holster body having an interior cavity configured to receive and hold a clamping end of one of the battery clamps. The interior cavity of each holster is defined by opposing front and rear walls, and opposing side walls extending between the front and rear walls. The rear wall of each holster includes a second connector that cooperates with the first connector of the housing to attach the holster body to the housing.

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the Background.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified block diagram of an electronic battery tester in accordance with the present disclosure.

FIG. 2 is a more detailed block diagram of the battery tester of FIG. 1.

FIG. 3 is a simplified flow chart showing steps in accordance with the present disclosure.

FIG. 4 is a simplified block diagram of an example of a battery tester, in accordance with embodiments of the present disclosure.

FIG. 5 is an exploded isometric view of an example of a battery tester, in accordance with embodiments of the present disclosure.

FIGS. 6 and 7 are top views of the battery tester of FIG. 5 respectively with a clamp outside and received within a holster of the battery tester, in accordance with embodiments of the present disclosure.

FIG. 8 is an isometric view of the battery tester of FIG. 5 without battery clamps, in accordance with embodiments of the present disclosure.

FIGS. 9 and 10 are side cross-sectional views of the battery tester of FIG. 4, in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Embodiments of the present disclosure relate to a battery tester having holsters for securing battery clamps when not in use. Before describing embodiments of holsters, examples of a battery tester and monitoring system will be described.

Since the introduction and manufacture of SLI (Starting/lighting/ignition) batteries for automobiles, testing methodology has relied primarily on BCI (Battery Council International) supported standards to measure the overall condition of the battery using hydrometer, load, and voltage drop testing standards.

With an increase in battery sales by mass retailers and service providers, these traditional methods have been replaced by various electronic testers and fast chargers using various technologies including conductance, impedance, load, light, charge acceptance to both test and recovery discharged batteries, etc.

The Battery Council International has also published information on the average battery life calculations by geographic area. Manufacturers of test equipment, retailers, battery manufacturers, and service providers have been reluctant to modify specific test algorithms or charge recovery times solely based on the battery age or sell date, treating all batteries the same as presented for testing, charge, recovery, and in the determination of warranty acceptance. Class action lawsuits, fines, and criminal charges relating unscrupulous selling methods, sales incentive awards, or kickbacks for increasing battery sales have additionally contributed to the reluctance of retailers, battery manufacturers, service providers, and tester manufacturers in introducing additional manually inputted criteria that could be manipulated by users of the equipment to deceive customers or construe an environment that could lead to misrepresentation of results to the customer. Potential liabilities, risks, and past legal issues outweighed the benefits generated by incorporating battery age into the testing criteria that would directly influence the testing algorithm in the determination of the batteries true condition and need for possible replacement.

Recent methodologies of incorporating battery age as part of the test process include only the printing of average battery life, the triggering of marginal battery indication, or additional information concerning the tested battery such as cold weather start performance, but do not, in general, influence or change the actual testing algorithms, criteria, recovery times, recovery methods, or analysis of the battery presented based on the battery's age or amount of time the battery has been in use. In general, all batteries are tested and charged in the same manner regardless of the age, warranty, non-warranty, or quality level classification (Good, Better, Best series) of battery purchased as presented to the testers or chargers.

While past practices have been regarded as acceptable methods for testing and charging batteries, advances in battery manufacturing technology and tighter quality control standards have significantly reduced manufacturing quality defects in battery production. Improved transportation infrastructure, packaging, and shipment methods have reduced damage during transit. Better management of stock rotation, turns, and retail rack systems has reduced potential problems created with the storage of the batteries prior to sale.

Advances in point of sale (POS) systems have also greatly advanced the information available to retailers, OEM's, distributors, and service providers regarding the manufacturer, sell date, and useful life span. Several methodologies now exist to extract this information about the battery through scanning or input of serial number identifiers, date codes; RFID tags, and bar-coding technology providing enhanced methods for determining battery age, sell date, and warranty tracking. Additionally, this information can be uploaded automatically to the testers through the use of bar code scanning, RFID, POS transfer of information which reduces the manual inputs necessary by the operator greatly reducing potential errors associated with past manual input testing practices.

While manufactured battery defects continue to decline, newer automobiles have seen their power requirements increase with the addition by OEM's of Electronic Control Units or ECM's, TCM's, on-board entertainment systems, communication systems, power systems, environmental, and other OEM installed systems. Additionally, consumers may add optional non-OEM devices to the vehicle requiring substantial power demands from the battery and charging system including, power chargers for cell phone communication, computers, video players, high powered audio amplifiers, GPS navigation systems, lighting systems, along with many other optional devices which can demand high power consumption from the vehicle electrical systems.

Many times, the vehicle's OEM electrical system may not have the capacity to supply all the vehicle power demands, relying on the battery to supplement these demands. Situations involving short distance driving, stop/go driving, extended idling, and operating the accessories with the vehicle without the engine running can significantly deplete the power reserve capacities of these batteries. Additionally, accessories left in the on position in an unintended manner can severely deplete the power reserves of the battery leading to a no-start situation with the vehicle.

With the complexity of these on-board systems and power demands for optional equipment it is not uncommon for a consumer to have a no-start situation occur and to assume that they need a new battery when in fact, the cause of the no-start situation was the result of excessive power demands or charging system problem causing the discharged battery condition. Many of these consumers will install or purchase a new battery only to have the same no-start or discharged battery condition occur or repeat itself, leading the customer to believe they have purchased a defective battery and asking for a free replacement under the terms of the free replacement warranty for manufacturing defect, as the battery will not start the vehicle in its heavily discharged state.

Conventional testing and fast charging methodology using the rating of the battery and other inputs or conditions could significantly create longer wait times for all batteries to be tested or charged to determine if the battery is recoverable. Additionally, the knowledge gained on the age of the battery can aid to successfully identifying the cause of the discharge so that the consumer can address and fix the issue so that the situation does not reoccur. Additionally, battery manufacturers and retailers can provide enhanced customer service and support to the consumer while reducing their warranty exposure on new battery sales. Battery age as an input can have a significant positive environmental impact in reduction of fossil fuels for the transport, recovery, recycling, and raw materials required by replacing these good batteries for consumers with another warranty replacement.

The current policies of replacement of good batteries by retailers and service providers are estimated in excess of 500 million dollars annually.

As a battery ages, its internal components gradually wear out through corrosion, disintegration and shedding. When this happens, its conductance typically drops until it reaches a point at which the performance of the battery becomes significantly degraded and can cause a vehicle to not start. Similarly, a new battery which has been recently installed in a vehicle and experienced significant discharge from a power drain from lights being left in the on position, doors left open, accessory power drains, or a damaged charging system may also fail to start the vehicle.

Treating and/or recovering an eight-year-old battery the same manner as a one week old battery greatly reduces the effectiveness of the equipment in determining the true battery condition in deeply discharges batteries. This leads to an increase in error rates, and lower recovery rates for deeply discharged batteries.

Through the input of battery age in the test process, custom algorithms can be added to the testers and diagnostic chargers allowing customized test and recovery processes to occur that can significantly increase the overall accuracy, speed, and recovery rates for good batteries, along with conveying important information to the operator and consumer regarding the potential reason for the no-start condition.

Below are examples of the use of battery age.

A battery submitted for testing is identified by the tester or charger as being sold within the last two days and analysis indicates the battery is in a severely discharged state. Knowing that the battery was recently manufactured and that quality defects make up less than 0.25% of return issues, the test algorithm is modified to indicate that charging is required. Similarly, in the use of a diagnostic charger, the algorithm is adjusted to allow for additional charge recovery time or modification of test/recovery algorithms in addition to communicating to the user specific outputs to aid the retailer or consumer in determining possible issues that could cause a battery to become severely discharged.

A consumer presenting a battery for testing that is eight years in age and in a discharged state would allow for tailoring of the test algorithm to seek out specific factors that are commonly found in older batteries such as sulfated conditions, plate or grid damage, bad-cell, or shorted conditions. The charge recovery rate for batteries of this age is substantially lower than the general population seen as sited in the previous two-day old battery example. Testing and charging both batteries in the same manner again reduces the effectiveness of the equipment, impacts overall accuracy rates, and could prolong the test and recovery process creating longer customer wait times. Through the use of the input of battery age, specific algorithms can be used to identify immediately to the customer the average life span for that type, in addition to specific test and charge recovery algorithms tailored for older batteries based on research of test & recovery methods for older batteries. These specific algorithms using battery age as an input will provide enhanced accuracy, faster test and recovery times, enhanced diagnostic output and recommendations for the user and consumer; and better efficiency of equipment in a retail, OEM, or service environment.

Age Input Methodologies:

Inputting age and/or sales date of the battery into the tester or diagnostic charger can use any appropriate technique. For example:

-   -   Unique serial Number ID on the battery     -   Unique Bar-Code on the Battery     -   Serial # tied to database     -   Unique Bar code tied to database     -   RFID Tag     -   RFID Tag tied to database     -   Receipt input—Manual     -   Receipt input—Bar Code     -   Receipt input—Database     -   Database—Customer ID—Phone, Name, customer #     -   Manual input—By User     -   Manual Input

FIG. 1 illustrates an electronic battery tester 16 which operates in accordance with one or more embodiments of the present disclosure. Tester 16 includes dynamic parameter measurement circuitry 2, which is configured to measure a dynamic parameter of battery 12 through first and second Kelvin connections 8A and 8B. Dynamic parameter measurement circuitry 2 measures a dynamic parameter, that is a parameter which is a function of a signal with a time varying component of battery 12, and provides a dynamic parameter output 4 to calculation circuitry 6. Examples of dynamic parameters include dynamic conductance resistance, reactance, susceptance, and their combinations. Calculation circuitry 6 receives the dynamic parameter output 4 and an optional rating 8, which relates to a rating of battery 12 and an empirical input variable 9. Based upon the optional rating, the empirical input variable and the measured dynamic parameter output 4, calculation circuitry 6 responsively provides a relative test output 11 of battery 12.

In one aspect of the present disclosure, the criteria used to test the storage battery 12 is adjusted based upon the age of the battery 12. For example, if battery 12 is a new battery, a more stringent test can be applied to battery 12.

FIG. 2 is a more detailed block diagram of circuitry 16 which operates in accordance with one embodiment of the present disclosure, and determines a dynamic parameter such as the conductance (G_(BAT)) of battery 12 and the voltage potential (V_(BAT)) between terminals 22 and 24 of battery 12. Circuitry 16 includes a forcing function such as current source 50, differential amplifier 52, analog-to-digital converter 54 and microprocessor 56. In this embodiment, dynamic parameter measurement circuitry 2 shown in FIG. 1 generally comprises source 50, amplifier 52, analog-to-digital converter 54, amplifier 70 and microprocessor 56. Calculation circuitry 6 generally comprises microprocessor 56. The general blocks shown in FIG. 1 can be implemented as desired and are not limited to the configurations shown in FIG. 2. Amplifier 52 is capacitively coupled to battery 12 through capacitors C₁ and C₂. Amplifier 52 has an output connected to an input of analog-to-digital converter 54. Microprocessor 56 is connected to system clock 58, memory 60 and analog-to-digital converter 54. Microprocessor 56 may also be connected to a pass/fail indicator. Microprocessor 56 is also capable of receiving an input from input device 66. The input can be the empirical input variable, a rating of the battery, or other data as desired.

In operation, current source 50 is controlled by microprocessor 56 and provides a current in the direction shown by the arrow in FIG. 2. This can be any type of time varying signal. Source 50 can be an active source or a passive source such as a resistance. Differential amplifier 52 is connected to terminals 22 and 24 of battery 12 through capacitors C₁ and C₂, respectively, and provides an output related to the voltage potential difference between terminals 22 and 24. In a preferred embodiment, amplifier 52 has a high input impedance. Circuitry 16 includes differential amplifier 70 having inverting and non-inverting inputs connected to terminals 24 and 22, respectively. Amplifier 70 is connected to measure the open circuit potential voltage (V_(BAT)) of battery 12 between terminals 22 and 24. The output of amplifier 70 is provided to analog-to-digital converter 54 such that the voltage across terminals 22 and 24 can be measured by microprocessor 56.

Circuitry 16 is connected to battery 12 through a four-point connection technique known as a Kelvin connection. This Kelvin connection allows current I to be injected into battery 12 through a first pair of terminals, while the voltage V across the terminals 22 and 24 is measured by a second pair of connections. Because very little current flows through amplifier 52, the voltage drop across the inputs to amplifier 52 is substantially identical to the voltage drop across terminals 22 and 24 of battery 12. The output of differential amplifier 52 is converted to a digital format and is provided to microprocessor 56. Microprocessor 56 operates at a frequency determined by system clock 58 and in accordance with programming instructions stored in memory 60.

Microprocessor 56 determines the conductance of battery 12 by applying a forcing function having a time varying component. The forcing function can be applied by current source 50 which operates as a forcing function source and may be any appropriate signal having a time varying component, including a transient signal. The forcing function source 50 can, for example, operate by selectively applying a load such as a resistance. The microprocessor determines the change in battery voltage due to the current pulse I using amplifier 52 and analog-to-digital converter 54. The value of current I generated by current source 50 is known and is stored in memory 60. In one embodiment, current I is obtained by applying a load to battery 12. Microprocessor 56 calculates the conductance of battery 12 using the following equation:

$\begin{matrix} {{Conductance} = {G_{BAT} = \frac{\Delta I}{\Delta V}}} & {{Equation}\mspace{14mu} 1} \end{matrix}$

where ΔI is the change in current flowing through battery 12 due to current source 50 and ΔV is the change in battery voltage due to applied current ΔI.

Microprocessor 56 operates in accordance with the present disclosure and determines the relative test output discussed herein. The relative test output can be provided on the data output. The data output can be a visual display or other device for providing information to an operator and/or can be an output provided to other circuitry.

As used herein, a dynamic parameter of the battery is a parameter which has been measured using an applied signal (either passively or actively) with a time varying component. Examples of dynamic parameters include dynamic resistance, conductance, reactance, susceptance and their combinations both real, imaginary and combinations, etc.

Embodiments of the present disclosure may be implemented using any appropriate technique. For simplicity, a single technique has been illustrated herein. However, other techniques may be used including implementation in all analog circuitry. Additionally, by using appropriate techniques, any dynamic parameter can be measured. In some embodiments, a desired output level of the battery is obtained, for example through an input.

FIG. 3 is a block diagram 100 showing steps in accordance with one embodiment of the present disclosure. These steps can be implemented using the circuitry shown in FIG. 2. For example, the steps can be implemented in microprocessor 56 in accordance with programming instructions stored in memory 60.

At block 102, the process is initiated and control is passed to block 104 where the battery tester 16 receives battery age information from input 66. This battery age information can be received through any appropriate techniques including a user input. The input may be a date, unique identifier of the battery, code identifier of the manufacture date, information related to a sale date, any information related to manufacture date, etc. The input can be through a manual input or through other non-manual techniques such as a barcode input, serial number input, a RFID (Radio Frequency Identification tag), input contained on a purchase receipt or warranty card, retrieved from a database based upon purchase information such as information which identifies the purchase, etc.

At block 106, battery test information is retrieved, for example, from memory 60. This test information can be a particular test criteria, a particular battery test, etc. including information stored in memory 60 of battery tester 106. The battery test information retrieved at block 106 is modified based upon the received age information at block 108. The test itself may be modified (in other words, different types of test are applied such as a load test, etc.) or steps in the test are modified, for example, the battery must be recharged prior to test. In another example, the test criteria are modified, in other words, the test result for a new battery may be indicated as a failure, whereas the same test result for an older battery may be considered a successful test.

At block 110, the battery test is performed. This battery test can be in accordance with any appropriate technique and is not limited to the tests described herein. An output from the battery test result is provided at block 112. This output can be provided locally or can be sent to a remote location, or to other electronic circuitry. The output may be in a human readable form or it may be in a form that is readable by machine. The output may include the received battery aging information or otherwise be based upon the battery age information. This may be in the form of the modified battery test result, or some other form. The output may be encrypted such that it is not easily modified in order to reduce falsified warranty claims. At block 114, the process terminates.

The age information can be used in any type of battery maintenance device and is not limited to a battery tester. For example, device 16 may comprise any type of battery maintenance device such as a battery tester or a charger, a combination of the two, a charger that includes diagnostic capabilities, etc.

Battery Clamp Holsters

FIGS. 4-10 illustrate examples of a battery tester 130, in accordance with embodiments of the present disclosure. FIG. 4 is a simplified block diagram of a battery tester 130, in accordance with embodiments of the present disclosure. In FIG. 4, hidden features and alternative positions of the battery clamps are shown in phantom lines. FIG. 5 is an exploded isometric view of an example of a battery tester 130, in accordance with embodiments of the present disclosure. FIGS. 6 and 7 are top views of the battery tester 130 of FIG. 5 respectively with a battery clamp received within a holster of the battery tester 130, in accordance with embodiments of the present disclosure. FIG. 8 is an isometric view of the battery tester 130 without the battery clamps, in accordance with embodiments of the present disclosure. FIGS. 9 and 10 are side cross-sectional views of the battery tester 130, in accordance with embodiments of the present disclosure.

The battery tester 130 generally includes a testing unit 132, a pair of battery clamps 134, and a pair of clamp holsters 136. In some of the figures, only a single battery clamp 134 is illustrated in order to simplify the drawings.

Each battery clamp 134 may take on any conventional form, and is configured to connect terminals 137 of a battery under test 139 (FIG. 4) to the testing unit 132 through a traditional connection, a Kelvin connection (e.g., connection 8A or 8B in FIG. 1), or another suitable connection. Each battery clamp 134 may be attached to the testing unit 132 through a suitable cable 135.

The testing unit 132 includes testing circuitry 141 that is configured to perform one or more battery tests on a battery 139 that is connected to the test unit 132 through the clamps 134, as indicated in FIG. 4. The testing circuitry 141 may take on any suitable form, such as circuitry that is similar to the tester 16 described above, or similar to the testing circuitry described in the battery tester examples in the references cited below. The testing performed by the circuitry 141 of the testing unit 132 may include a battery test in accordance with one or more embodiments described herein.

Each holster 136 is configured to receive one of the battery clamps 134 when they are not in use. This is illustrated in FIG. 4 by the clamps 134 shown in solid and phantom lines, and in FIG. 7. In some embodiments, each holster 136 includes a holster body 138 having an opening 140 at a receiving end 142 to an interior cavity 144, such as shown in FIG. 5. The interior cavity 144 is configured to receive and hold one of the clamps 134. In some embodiments, the interior cavity 144 is configured to receive and hold a clamping end 146 of the battery clamp 134, as shown in FIGS. 4 and 7. The holster body 138 also includes a distal end 148, which may be closed to protect the clamping end 146 of the battery clamp 134 that is received within the interior cavity 144, as shown in FIG. 7.

In some embodiments, the interior cavity 144 of the holster body 138 may be defined by a front wall 143, a rear wall 145 that is opposite the front wall 143, and opposing side walls 147 and 149 that extend between and connect to the front and rear walls 143 and 145, as best shown in FIG. 5. In some embodiments, these walls of the interior cavity 144 of the holster body 138 may approximately conform to the exterior of the clamping end 146 of the battery clamp 134 to prevent excessive movement of the battery clamp 134 once it is received within the holster 136. For example, the side walls 147 and 149 may be tapered from the receiving end 142 to the distal end 148 to better conform to the clamping end 146 of the clamps 134, as shown in FIG. 6.

In some embodiments, the testing unit 132 includes a housing 150 that is configured to support the holsters 136. The housing 150 and the holster body 138 may include cooperating connectors 151 that facilitate the attachment of the holster body 138 to the housing 150, as indicated in FIG. 4. In some embodiments, the cooperating connectors on the holster body 138 are keyed to the opposite sides of the housing 150 to prevent attachment of a holster 136 to the wrong side of the housing 150.

In one example, a cooperating connector 151 of the housing 150 includes a holster receiver 152 that may comprise a slot 154 having a shoulder 156, as shown in FIG. 8. The corresponding cooperating connector 151 of the holster body 138 may include a connecting tab 158 that extends from the rear wall 145 and is received within the slot 154 and secured to the housing 150 by the shoulder 156, as shown in FIGS. 8-10.

In some embodiments, the cooperating connectors 151 of the holster body 138 and the housing 150 include features that maintain the tab 158 within the slot 154. In one embodiment, the slot 154 and the tab 158 are tapered to provide a press-fit securement of the holster body 138 to the housing 150.

In another embodiment, the housing 150 may include a detent 162, such as in a side wall or surface 164 that is configured to receive a locking tab 166 extending from the side wall 147 of the holster body 138 when the tab 158 extending from the rear wall 145 of the holster body 138 is fully received within the slot 154. The tab 166 may extend from a live hinge 170 that forms a portion of the side wall 147. When the holster body 138 is attached to the housing 150 by sliding the tab 158 into the slot 154, the tab 166 snaps into the detent or groove 162 and prevents the detachment of the holster body 138 from the housing 150, such as by preventing the connecting tab 158 from sliding out of the slot 154. Thus, the engagement between detent 162 and the locking tab 166 secures the holster body 138 to the housing 150. The holster body 138 may be detached from the housing 150 by pulling the live hinge 170 away from the side wall 164 of the housing 150, and sliding the holster body 138 such that the tab 158 is removed from the slot 154.

In some embodiments, the battery tester 130 magnetically secures the battery clamps 134 within the holsters 136 using one or more magnets 172 (hereinafter “magnet”), such as indicated in FIG. 4. In one example, the housing 150 of the testing unit 132 includes sockets 174 that are each configured to receive one of the magnet 172, as best shown in FIGS. 5, 9 and 10. The socket 174 and the received magnet 172 may be positioned adjacent the receiving end 142 of the holster 136 or another location to position the magnet 172 adjacent a portion 177 (e.g., a steel portion) of the battery clamp 134 when it is received within the holster 136, such as shown in FIGS. 9 and 10. The magnetic attraction between the magnet 172 and the portion 177 of the battery clamp 134 operates to secure the battery clamp 134 within the holster 136, while allowing a user to quickly remove the battery clamp 134 from the holster 136 by hand. Thus, the magnet 172 assists in securing the battery clamp 134 within the holster 136 when the testing unit is jostled or oriented at an angle that would otherwise cause the clamps 134 to fall out of the holster 136.

The magnet 172 may be secured within the socket 174 of the housing 150 using any suitable technique, such as an adhesive or a press-fit connection. In some embodiments, the magnet 172 is protected from egress from the socket 174 by the holster body 138. For example, edges of a notch 178 formed in the rear wall 145 of the holster body 138 may engage the top surface 176 of the magnet 172 when it is received within the socket 174.

In some embodiments, a top surface 176 of the magnet 172 may be flush with the top edge of the socket 174 of the housing 150, such as shown in FIG. 10. When the battery clamp 134 is received within the holster 136, the portion 177 of the battery clamp 134 is preferably positioned in contact with or in close proximity to the top surface 176 of the magnet 172 to improve the magnetic attraction of the clamp 134 to the magnet 172, and improve the securement of the clamp 134 within the holster 136. In one embodiment, the portion 177 may be accommodated by the notch 178 formed in the holster body 138 to allow the portion 177 to be placed in contact with the surface 176 of the magnet 172, or at least is closer in proximity to the surface 176 than would be possible if the notch 178 was not present, as shown in FIG. 9.

Alternatively, the top surface 176 of the magnet 172 may extend above the top edge of the socket 174 and, thus, project from the housing 150 toward the interior cavity 144 of the holster 136. This projection of the magnet 172 may be accommodated by the notch 178 formed in the holster body 138, through which the top surface 176 of the magnet 172 may extend. This allows the top surface 176 of the magnet 172 to be placed closer to the battery clamp 134 when it is received within the holster 136 than would be possible if the notch 178 was not present. This reduction or elimination of a gap between the top surface 176 of the magnet 172 and the battery clamp 134, such as a steel portion of the battery clamp 134, provides an increase in the magnetic attraction between the magnet 172 and the battery clamp 134 than would be possible if a larger gap existed. As a result, the reduction or elimination of such a gap by projecting the top surface 176 of the magnet 172 into or toward the interior cavity 144 of the holster 136 improves the securement of the battery clamp 134 within the holster 136.

Electronic battery testers are known in the art and used to test storage batteries. Various examples of such testers, testing circuitry, battery tests, and other related technology are described in the following references, all of which are incorporated herein by reference in their entireties: U.S. Pat. No. 3,873,911, issued Mar. 25, 1975, to Champlin; U.S. Pat. No. 3,909,708, issued Sep. 30, 1975, to Champlin; U.S. Pat. No. 4,816,768, issued Mar. 28, 1989, to Champlin; U.S. Pat. No. 4,825,170, issued Apr. 25, 1989, to Champlin; U.S. Pat. No. 4,881,038, issued Nov. 14, 1989, to Champlin; U.S. Pat. No. 4,912,416, issued Mar. 27, 1990, to Champlin; U.S. Pat. No. 5,140,269, issued Aug. 18, 1992, to Champlin; U.S. Pat. No. 5,343,380, issued Aug. 30, 1994; U.S. Pat. No. 5,572,136, issued Nov. 5, 1996; U.S. Pat. No. 5,574,355, issued Nov. 12, 1996; U.S. Pat. No. 5,583,416, issued Dec. 10, 1996; U.S. Pat. No. 5,585,728, issued Dec. 17, 1996; U.S. Pat. No. 5,589,757, issued Dec. 31, 1996; U.S. Pat. No. 5,592,093, issued Jan. 7, 1997; U.S. Pat. No. 5,598,098, issued Jan. 28, 1997; U.S. Pat. No. 5,656,920, issued Aug. 12, 1997; U.S. Pat. No. 5,757,192, issued May 26, 1998; U.S. Pat. No. 5,821,756, issued Oct. 13, 1998; U.S. Pat. No. 5,831,435, issued Nov. 3, 1998; U.S. Pat. No. 5,871,858, issued Feb. 16, 1999; U.S. Pat. No. 5,914,605, issued Jun. 22, 1999; U.S. Pat. No. 5,945,829, issued Aug. 31, 1999; U.S. Pat. No. 6,002,238, issued Dec. 14, 1999; U.S. Pat. No. 6,037,751, issued Mar. 14, 2000; U.S. Pat. No. 6,037,777, issued Mar. 14, 2000; U.S. Pat. No. 6,051,976, issued Apr. 18, 2000; U.S. Pat. No. 6,081,098, issued Jun. 27, 2000; U.S. Pat. No. 6,091,245, issued Jul. 18, 2000; U.S. Pat. No. 6,104,167, issued Aug. 15, 2000; U.S. Pat. No. 6,137,269, issued Oct. 24, 2000; U.S. Pat. No. 6,163,156, issued Dec. 19, 2000; U.S. Pat. No. 6,172,483, issued Jan. 9, 2001; U.S. Pat. No. 6,172,505, issued Jan. 9, 2001; U.S. Pat. No. 6,222,369, issued Apr. 24, 2001; U.S. Pat. No. 6,225,808, issued May 1, 2001; U.S. Pat. No. 6,249,124, issued Jun. 19, 2001; U.S. Pat. No. 6,259,254, issued Jul. 10, 2001; U.S. Pat. No. 6,262,563, issued Jul. 17, 2001; U.S. Pat. No. 6,294,896, issued Sep. 25, 2001; U.S. Pat. No. 6,294,897, issued Sep. 25, 2001; U.S. Pat. No. 6,304,087, issued Oct. 16, 2001; U.S. Pat. No. 6,310,481, issued Oct. 30, 2001; U.S. Pat. No. 6,313,607, issued Nov. 6, 2001; U.S. Pat. No. 6,313,608, issued Nov. 6, 2001; U.S. Pat. No. 6,316,914, issued Nov. 13, 2001; U.S. Pat. No. 6,323,650, issued Nov. 27, 2001; U.S. Pat. No. 6,329,793, issued Dec. 11, 2001; U.S. Pat. No. 6,331,762, issued Dec. 18, 2001; U.S. Pat. No. 6,332,113, issued Dec. 18, 2001; U.S. Pat. No. 6,351,102, issued Feb. 26, 2002; U.S. Pat. No. 6,359,441, issued Mar. 19, 2002; U.S. Pat. No. 6,363,303, issued Mar. 26, 2002; U.S. Pat. No. 6,377,031, issued Apr. 23, 2002; U.S. Pat. No. 6,392,414, issued May 21, 2002; U.S. Pat. No. 6,417,669, issued Jul. 9, 2002; U.S. Pat. No. 6,424,158, issued Jul. 23, 2002; U.S. Pat. No. 6,441,585, issued Aug. 17, 2002; U.S. Pat. No. 6,437,957, issued Aug. 20, 2002; U.S. Pat. No. 6,445,158, issued Sep. 3, 2002; U.S. Pat. Nos. 6,456,045; 6,466,025, issued Oct. 15, 2002; U.S. Pat. No. 6,465,908, issued Oct. 15, 2002; U.S. Pat. No. 6,466,026, issued Oct. 15, 2002; U.S. Pat. No. 6,469,511, issued Nov. 22, 2002; U.S. Pat. No. 6,495,990, issued Dec. 17, 2002; U.S. Pat. No. 6,497,209, issued Dec. 24, 2002; U.S. Pat. No. 6,507,196, issued Jan. 14, 2003; U.S. Pat. No. 6,534,993; issued Mar. 18, 2003; U.S. Pat. No. 6,544,078, issued Apr. 8, 2003; U.S. Pat. No. 6,556,019, issued Apr. 29, 2003; U.S. Pat. No. 6,566,883, issued May 20, 2003; U.S. Pat. No. 6,586,941, issued Jul. 1, 2003; U.S. Pat. No. 6,597,150, issued Jul. 22, 2003; U.S. Pat. No. 6,621,272, issued Sep. 16, 2003; U.S. Pat. No. 6,623,314, issued Sep. 23, 2003; U.S. Pat. No. 6,633,165, issued Oct. 14, 2003; U.S. Pat. No. 6,635,974, issued Oct. 21, 2003; U.S. Pat. No. 6,696,819, issued Feb. 24, 20144; U.S. Pat. No. 6,707,303, issued Mar. 16, 2004; U.S. Pat. No. 6,737,831, issued May 18, 2004; U.S. Pat. No. 6,744,149, issued Jun. 1, 2004; U.S. Pat. No. 6,759,849, issued Jul. 6, 2004; U.S. Pat. No. 6,781,382, issued Aug. 24, 2004; U.S. Pat. No. 6,788,025, filed Sep. 7, 2004; U.S. Pat. No. 6,795,782, issued Sep. 21, 2004; U.S. Pat. No. 6,805,090, filed Oct. 19, 2004; U.S. Pat. No. 6,806,716, filed Oct. 19, 2004; U.S. Pat. No. 6,850,037, filed Feb. 1, 2005; U.S. Pat. No. 6,850,037, issued Feb. 1, 2005; U.S. Pat. No. 6,871,151, issued Mar. 22, 2005; U.S. Pat. No. 6,885,195, issued Apr. 26, 2005; U.S. Pat. No. 6,888,468, issued May 3, 2005; U.S. Pat. No. 6,891,378, issued May 10, 2005; U.S. Pat. No. 6,906,522, issued Jun. 14, 2005; U.S. Pat. No. 6,906,523, issued Jun. 14, 2005; U.S. Pat. No. 6,909,287, issued Jun. 21, 2005; U.S. Pat. No. 6,914,413, issued Jul. 5, 2005; U.S. Pat. No. 6,913,483, issued Jul. 5, 2005; U.S. Pat. No. 6,930,485, issued Aug. 16, 2005; U.S. Pat. No. 6,933,727, issued Aug. 23, 200; U.S. Pat. No. 6,941,234, filed Sep. 6, 2005; U.S. Pat. No. 6,967,484, issued Nov. 22, 2005; U.S. Pat. No. 6,998,847, issued Feb. 14, 2006; U.S. Pat. No. 7,003,410, issued Feb. 21, 2006; U.S. Pat. No. 7,003,411, issued Feb. 21, 2006; U.S. Pat. No. 7,012,433, issued Mar. 14, 2006; U.S. Pat. No. 7,015,674, issued Mar. 21, 2006; U.S. Pat. No. 7,034,541, issued Apr. 25, 2006; U.S. Pat. No. 7,039,533, issued May 2, 2006; U.S. Pat. No. 7,058,525, issued Jun. 6, 2006; U.S. Pat. No. 7,081,755, issued Jul. 25, 2006; U.S. Pat. No. 7,106,070, issued Sep. 12, 2006; U.S. Pat. No. 7,116,109, issued Oct. 3, 2006; U.S. Pat. No. 7,119,686, issued Oct. 10, 2006; and U.S. Pat. No. 7,126,341, issued Oct. 24, 2006; U.S. Pat. No. 7,154,276, issued Dec. 26, 2006; U.S. Pat. No. 7,198,510, issued Apr. 3, 2007; U.S. Pat. No. 7,363,175, issued Apr. 22, 2008; U.S. Pat. No. 7,208,914, issued Apr. 24, 2007; U.S. Pat. No. 7,246,015, issued Jul. 17, 2007; U.S. Pat. No. 7,295,936, issued Nov. 13, 2007; U.S. Pat. No. 7,319,304, issued Jan. 15, 2008; U.S. Pat. No. 7,363,175, issued Apr. 22, 2008; U.S. Pat. No. 7,398,176, issued Jul. 8, 2008; U.S. Pat. No. 7,408,358, issued Aug. 5, 2008; U.S. Pat. No. 7,425,833, issued Sep. 16, 2008; U.S. Pat. No. 7,446,536, issued Nov. 4, 2008; U.S. Pat. No. 7,479,763, issued Jan. 20, 2009; U.S. Pat. No. 7,498,767, issued Mar. 3, 2009; U.S. Pat. No. 7,501,795, issued Mar. 10, 2009; U.S. Pat. No. 7,505,856, issued Mar. 17, 2009; U.S. Pat. No. 7,545,146, issued Jun. 9, 2009; U.S. Pat. No. 7,557,586, issued Jul. 7, 2009; U.S. Pat. No. 7,595,643, issued Sep. 29, 2009; U.S. Pat. No. 7,598,699, issued Oct. 6, 2009; U.S. Pat. No. 7,598,744, issued Oct. 6, 2009; U.S. Pat. No. 7,598,743, issued Oct. 6, 2009; U.S. Pat. No. 7,619,417, issued Nov. 17, 2009; U.S. Pat. No. 7,642,786, issued Jan. 5, 2010; U.S. Pat. No. 7,642,787, issued Jan. 5, 2010; U.S. Pat. No. 7,656,162, issued Feb. 2, 2010; U.S. Pat. No. 7,688,074, issued Mar. 30, 2010; U.S. Pat. No. 7,705,602, issued Apr. 27, 2010; U.S. Pat. No. 7,706,992, issued Apr. 27, 2010; U.S. Pat. No. 7,710,119, issued May 4, 2010; U.S. Pat. No. 7,723,993, issued May 25, 2010; U.S. Pat. No. 7,728,597, issued Jun. 1, 2010; U.S. Pat. No. 7,772,850, issued Aug. 10, 2010; U.S. Pat. No. 7,774,151, issued Aug. 10, 2010; U.S. Pat. No. 7,777,612, issued Aug. 17, 2010; U.S. Pat. No. 7,791,348, issued Sep. 7, 2010; U.S. Pat. No. 7,808,375, issued Oct. 5, 2010; U.S. Pat. No. 7,924,015, issued Apr. 12, 2011; U.S. Pat. No. 7,940,053, issued May 10, 2011; U.S. Pat. No. 7,940,052, issued May 10, 2011; U.S. Pat. No. 7,959,476, issued Jun. 14, 2011; U.S. Pat. No. 7,977,914, issued Jul. 12, 2011; U.S. Pat. No. 7,999,505, issued Aug. 16, 2011; U.S. Pat. No. D643,759, issued Aug. 23, 2011; U.S. Pat. No. 8,164,343, issued Apr. 24, 2012; U.S. Pat. No. 8,198,900, issued Jun. 12, 2012; U.S. Pat. No. 8,203,345, issued Jun. 19, 2012; U.S. Pat. No. 8,237,448, issued Aug. 7, 2012; U.S. Pat. No. 8,306,690, issued Nov. 6, 2012; U.S. Pat. No. 8,344,685, issued Jan. 1, 2013; U.S. Pat. No. 8,436,619, issued May 7, 2013; U.S. Pat. No. 8,442,877, issued May 14, 2013; U.S. Pat. No. 8,493,022, issued Jul. 23, 2013; U.S. Pat. No. D687,727, issued Aug. 13, 2013; U.S. Pat. No. 8,513,949, issued Aug. 20, 2013; U.S. Pat. No. 8,674,654, issued Mar. 18, 2014; U.S. Pat. No. 8,674,711, issued Mar. 18, 2014; U.S. Pat. No. 8,704,483, issued Apr. 22, 2014; U.S. Pat. No. 8,738,309, issued May 27, 2014; U.S. Pat. No. 8,754,653, issued Jun. 17, 2014; U.S. Pat. No. 8,872,516, issued Oct. 28, 2014; U.S. Pat. No. 8,872,517, issued Oct. 28, 2014; U.S. Pat. No. 8,958,998, issued Feb. 17, 2015; U.S. Pat. No. 8,963,550, issued Feb. 24, 2015; U.S. Pat. No. 9,018,958, issued Apr. 28, 2015; U.S. Pat. No. 9,052,366, issued Jun. 9, 2015; U.S. Pat. No. 9,201,120, issued Dec. 1, 2015; U.S. Pat. No. 9,229,062, issued Jan. 5, 20126; U.S. Pat. No. 9,244,100, issued Jan. 26, 2016; U.S. Pat. No. 9,274,157, issued Mar. 1, 2016; U.S. Pat. No. 9,312,575, issued Apr. 12, 2016; U.S. Pat. No. 9,335,362, issued May 10, 2016; U.S. Pat. No. 9,425,487, issued Aug. 23, 2016; U.S. Pat. No. 9,419,311, issued Aug. 16, 2016; U.S. Pat. No. 9,496,720, issued Nov. 15, 2016; U.S. Pat. No. 9,588,185, issued Mar. 7, 2017; U.S. Pat. No. 9,923,289, issued Mar. 20, 2018; U.S. Pat. No. 9,966,676, issued May 8, 2018; U.S. Pat. No. 10,046,649, issued Aug. 14, 2018; U.S. Pat. No. 10,222,397, issued Mar. 5, 2019; U.S. Pat. No. 10,317,468, issued Jun. 11, 2019; U.S. Pat. No. 10,429,449, issued Oct. 1, 2019; U.S. Pat. No. 10,473,555, issued Nov. 12, 2019; U.S. Pat. No. 10,608,353, issued Mar. 31, 2020; U.S. Pat. No. 10,843,574, issued Nov. 24, 2020; U.S. Ser. No. 09/780,146, filed Feb. 9, 2001, entitled STORAGE BATTERY WITH INTEGRAL BATTERY TESTER; U.S. Ser. No. 09/756,638, filed Jan. 8, 2001, entitled METHOD AND APPARATUS FOR DETERMINING BATTERY PROPERTIES FROM COMPLEX IMPEDANCE/ADMITTANCE; U.S. Ser. No. 09/862,783, filed May 21, 2001, entitled METHOD AND APPARATUS FOR TESTING CELLS AND BATTERIES EMBEDDED IN SERIES/PARALLEL SYSTEMS; U.S. Ser. No. 09/880,473, filed Jun. 13, 2001; entitled BATTERY TEST MODULE; U.S. Ser. No. 10/109,734, filed Mar. 28, 2002, entitled APPARATUS AND METHOD FOR COUNTERACTING SELF DISCHARGE IN A STORAGE BATTERY; U.S. Ser. No. 10/263,473, filed Oct. 2, 2002, entitled ELECTRONIC BATTERY TESTER WITH RELATIVE TEST OUTPUT; U.S. Ser. No. 09/653,963, filed Sep. 1, 2000, entitled SYSTEM AND METHOD FOR CONTROLLING POWER GENERATION AND STORAGE; U.S. Ser. No. 10/174,110, filed Jun. 18, 2002, entitled DAYTIME RUNNING LIGHT CONTROL USING AN INTELLIGENT POWER MANAGEMENT SYSTEM; U.S. Ser. No. 10/258,441, filed Apr. 9, 2003, entitled CURRENT MEASURING CIRCUIT SUITED FOR BATTERIES; U.S. Ser. No. 10/681,666, filed Oct. 8, 2003, entitled ELECTRONIC BATTERY TESTER WITH PROBE LIGHT; U.S. Ser. No. 11/207,419, filed Aug. 19, 2005, entitled SYSTEM FOR AUTOMATICALLY GATHERING BATTERY INFORMATION FOR USE DURING BATTERY TESTER/CHARGING, U.S. Ser. No. 11/356,443, filed Feb. 16, 2006, entitled ELECTRONIC BATTERY TESTER WITH NETWORK COMMUNICATION; U.S. Ser. No. 12/697,485, filed Feb. 1, 2010, entitled ELECTRONIC BATTERY TESTER; U.S. Ser. No. 12/769,911, filed Apr. 29, 2010, entitled STATIONARY BATTERY TESTER; U.S. Ser. No. 13/098,661, filed May 2, 2011, entitled METHOD AND APPARATUS FOR MEASURING A PARAMETER OF A VEHICLE ELECTRICAL SYSTEM; U.S. Ser. No. 13/152,711, filed Jun. 3, 2011, entitled BATTERY PACK MAINTENANCE FOR ELECTRIC VEHICLE; U.S. Ser. No. 14/039,746, filed Sep. 27, 2013, entitled BATTERY PACK MAINTENANCE FOR ELECTRIC VEHICLE; U.S. Ser. No. 14/565,689, filed Dec. 10, 2014, entitled BATTERY TESTER AND BATTERY REGISTRATION TOOL; U.S. Ser. No. 15/017,887, filed Feb. 8, 2016, entitled METHOD AND APPARATUS FOR MEASURING A PARAMETER OF A VEHICLE ELECTRICAL SYSTEM; U.S. Ser. No. 15/049,483, filed Feb. 22, 2016, entitled BATTERY TESTER FOR ELECTRIC VEHICLE; U.S. Ser. No. 15/077,975, filed Mar. 23, 2016, entitled BATTERY MAINTENANCE SYSTEM; U.S. Ser. No. 15/149,579, filed May 9, 2016, entitled BATTERY TESTER FOR ELECTRIC VEHICLE; U.S. Ser. No. 15/791,772, field Oct. 24, 2017, entitled ELECTRICAL LOAD FOR ELECTRONIC BATTERY TESTER AND ELECTRONIC BATTERY TESTER INCLUDING SUCH ELECTRICAL LOAD; U.S. Ser. No. 16/021,538, filed Jun. 28, 2018, entitled BATTERY PACK MAINTENANCE FOR ELECTRIC VEHICLE; U.S. Ser. No. 16/056,991, filed Aug. 7, 2018, entitled HYBRID AND ELECTRIC VEHICLE BATTERY PACK MAINTENANCE DEVICE, U.S. Ser. No. 16/253,526, filed Jan. 22, 2019, entitled HIGH CAPACITY BATTERY BALANCER; U.S. Ser. No. 16/253,549, filed Jan. 22, 2019, entitled HYBRID AND ELECTRIC VEHICLE BATTERY PACK MAINTENANCE DEVICE; U.S. Ser. No. 16/297,975, filed Mar. 11, 2019, entitled HIGH USE BATTERY PACK MAINTENANCE; U.S. Ser. No. 16/695,705, filed Nov. 26, 2019, entitled BATTERY RATING VERSUS OEM SPECIFICATION; U.S. Ser. No. 16/943,120, filed Jul. 30, 2020 entitled TIRE TREAD GAUGE USING VISUAL INDICATOR; U.S. Ser. No. 17/086,629, filed Nov. 2, 2020, entitled HYBRID AND ELECTRIC VEHICLE BATTERY PACK MAINTENANCE DEVICE; U.S. Ser. No. 17/088,824, filed Nov. 4, 2020, entitled SYSTEM FOR CHARGING A SERIES OF CONNECTED BATTERIES; U.S. Ser. No. 17/090,129, filed Nov. 5, 2020 entitled BATTERY PACK MAINTENANCE SYSTEM; U.S. Ser. No. 17/136,600, filed Dec. 29, 2020, entitled INTELLIGENT MODULE INTERFACE FOR BATTERY MAINTENANCE DEVICE; all of which are incorporated herein by reference in their entireties.

Although embodiments of the present disclosure have been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the present disclosure. 

What is claimed is:
 1. A battery tester comprising: a pair of battery clamps, each clamp configured to connect to a terminal of a battery; a testing unit comprising testing circuitry connected to the battery clamps, the testing circuitry configured to perform one or more battery tests on a battery connected to the battery clamps; and a pair of holsters attached to a housing of the testing unit, each holster configured to receive and hold one of the battery clamps.
 2. The battery tester of claim 1, wherein each holster includes a holster body having an interior cavity configured to receive and hold a clamping end of one of the battery clamps.
 3. The battery tester of claim 2, wherein each holster body includes a closed distal end that is opposite an open receiving end, through which the clamping end is received into the interior cavity.
 4. The battery tester of claim 2, further comprising a pair of magnets, each attached to the housing adjacent one of the holsters and configured to magnetically secure one of the battery clamps within the holster.
 5. The battery tester of claim 4, wherein each of the magnets includes an exposed top surface.
 6. The battery tester of claim 5, wherein the top surface of each magnet is exposed through a portion of the corresponding holster bodies.
 7. The battery tester of claim 6, wherein each battery clamp includes a portion that contacts the top surface of one of the magnets through the portion of the holster body when the battery clamp is received within one of the holsters.
 8. The battery tester of claim 7, wherein each portion of the holster bodies comprises a notch extending around at least a portion of a perimeter of the corresponding magnet, wherein the portion of each battery clamp extends through the notch and contacts the top surface of the magnet when the battery clamp is received within one of the holsters.
 9. The battery tester of claim 2, wherein: the interior cavity of each of the holster bodies is defined by opposing front and rear walls and opposing side walls extending between the front and rear walls; the housing includes a pair of first connectors; the rear wall of each holster body includes a second connector; and the first and second connectors cooperate to attach the holster bodies to the housing.
 10. The battery tester of claim 9, wherein one of the first and second connectors includes a slot, and the other of the first and second connectors includes a connecting tab that is received within the slot to attach the holster bodies to the housing.
 11. The battery tester of claim 10, wherein: one of the side walls of each holster body includes a locking tab extending from a live hinge; and the housing includes a pair of detents, each of which receives the locking tab of one of the holster bodies and prevents the detachment of the holster body from the housing.
 12. A battery tester comprising: a pair of battery clamps, each clamp configured to connect to a terminal of a battery; a testing unit comprising testing circuitry connected to the battery clamps, the testing circuitry configured to perform one or more battery tests on a battery connected to the battery clamps; a housing including a pair of magnets; and a pair of holsters attached to the housing, each holster including a holster body having an interior cavity configured to receive and hold a clamping end of one of the battery clamps, wherein each magnet is configured to magnetically secure one of the battery clamps within the interior cavity of one of the holsters.
 13. The battery tester of claim 12, wherein each of the magnets includes an exposed top surface.
 14. The battery tester of claim 13, wherein the top surface of each magnet is exposed through a portion of the corresponding holster bodies.
 15. The battery tester of claim 14, wherein each battery clamp includes a portion that contacts the top surface of one of the magnets through the portion of the holster body when the battery clamp is received within one of the holsters.
 16. The battery tester of claim 15, wherein: the interior cavity of each of the holster bodies is defined by opposing front and rear walls and opposing side walls extending between the front and rear walls; the housing includes a pair of first connectors; the rear wall of each holster body includes a second connector; and the first and second connectors cooperate to attach the holster bodies to the housing.
 17. A battery tester comprising: a pair of battery clamps, each clamp configured to connect to a terminal of a battery; a testing unit comprising testing circuitry connected to the battery clamps, the testing circuitry configured to perform one or more battery tests on a battery connected to the battery clamps; a housing having a pair of first connectors; and a pair of holsters, each holster including a holster body having an interior cavity configured to receive and hold a clamping end of one of the battery clamps, the interior cavity defined by opposing front and rear walls, and opposing side walls extending between the front and rear walls, each rear wall including a second connector, wherein the first and second connectors cooperate to attach the holster bodies to the housing.
 18. The battery tester of claim 17, wherein one of the first and second connectors includes a slot, and the other of the first and second connectors includes a connecting tab that is received within the slot to attach the holster bodies to the housing.
 19. The battery tester of claim 18, wherein: one of the side walls of each holster body includes a locking tab extending from a live hinge; and the housing includes a pair of detents, each of which receives the locking tab of one of the holster bodies and prevents the detachment of the holster body from the housing.
 20. The battery tester of claim 19, wherein: the housing includes a pair of magnets, each magnetic having a top surface; and each battery clamp includes a portion that contacts the top surface of one of the magnets through a portion of the holster body when the battery clamp is received within one of the holsters. 